Customs and Border Protection officials plan to shut down several lanes of traffic through the border into San Diego in anticipation of the caravan, according to the Los Angeles Times.

• The Trump administration has instituted a new rule, targeted at these migrants, that will prevent anyone who crosses the border illegally from gaining asylum. This is likely to lead to overcrowding at ports of entry that are not designed for processing and holding hundreds — or thousands — of new asylum-seekers.

What's next: The port of entry between Tijuana and San Diego is already at capacity, meaning that these migrants will likely have long wait times in Mexico until they can even make an asylum claim.

By the numbers: More than 70% of Honduran, Salvadoran and Guatemalan asylum-seekers were denied defensive asylum in the U.S. between FY 2012 and FY 2017, according to data collected by the Transactional Records Access Clearinghouse at Syracuse University.

• And only one-quarter of all affirmative asylum applications were approved in the first three quarters of FY 2018, according to data from USCIS.

Go deeper:

• What happens when Caravan members apply for asylum
• What the military can and cannot do at the border
• The big picture: Caravan of Honduran immigrants advances into Mexico